Weak Integrability Breaking: Chaos with Integrability Signature in Coherent Diffusion
Weak Integrability Breaking: Chaos with Integrability Signature in Coherent Diffusion
We study how perturbations affect dynamics of integrable many-body quantum systems, causing transition from integrability to chaos. Looking at spin transport in the Heisenberg chain with impurities we find that in the thermodynamic limit transport gets diffusive already at an infinitesimal perturbation. Small extensive perturbations therefore cause an immediate transition …